move writeTimeout from mysqlConn to buffer

buffer.go

@@ -23,10 +23,11 @@ const maxCachedBufSize = 256 * 1024
 // The buffer is similar to bufio.Reader / Writer but zero-copy-ish
 // Also highly optimized for this particular use case.
 type buffer struct {
-	buf       []byte // read buffer.
-	cachedBuf []byte // buffer that will be reused. len(cachedBuf) <= maxCachedBufSize.
-	nc        net.Conn
-	timeout   time.Duration
+	buf          []byte // read buffer.
+	cachedBuf    []byte // buffer that will be reused. len(cachedBuf) <= maxCachedBufSize.
+	nc           net.Conn
+	readTimeout  time.Duration
+	writeTimeout time.Duration
 }
 
 // newBuffer allocates and returns a new buffer.
@@ -64,8 +65,8 @@ func (b *buffer) fill(need int) error {
 	copy(dest[:n], b.buf)
 
 	for {
-		if b.timeout > 0 {
-			if err := b.nc.SetReadDeadline(time.Now().Add(b.timeout)); err != nil {
+		if b.readTimeout > 0 {
+			if err := b.nc.SetReadDeadline(time.Now().Add(b.readTimeout)); err != nil {
 				return err
 			}
 		}
@@ -159,5 +160,10 @@ func (b *buffer) store(buf []byte) {
 // writePackets is a proxy function to nc.Write.
 // This is used to make the buffer type compatible with compressed I/O.
 func (b *buffer) writePackets(packets []byte) (int, error) {
+	if b.writeTimeout > 0 {
+		if err := b.nc.SetWriteDeadline(time.Now().Add(b.writeTimeout)); err != nil {
+			return 0, err
+		}
+	}
 	return b.nc.Write(packets)
 }

compress.go

@@ -195,7 +195,7 @@ func (c *compIO) writePackets(packets []byte) (int, error) {
 			}
 		}
 
-		if err := c.mc.writeCompressedPacket(buf.Bytes(), uncompressedLen); err != nil {
+		if err := c.writeCompressedPacket(buf.Bytes(), uncompressedLen); err != nil {
 			return 0, err
 		}
 		dataLen -= payloadLen
@@ -207,7 +207,8 @@ func (c *compIO) writePackets(packets []byte) (int, error) {
 
 // writeCompressedPacket writes a compressed packet with header.
 // data should start with 7 size space for header followed by payload.
-func (mc *mysqlConn) writeCompressedPacket(data []byte, uncompressedLen int) error {
+func (c *compIO) writeCompressedPacket(data []byte, uncompressedLen int) error {
+	mc := c.mc
 	comprLength := len(data) - 7
 	if debugTrace {
 		fmt.Printf(
@@ -220,7 +221,7 @@ func (mc *mysqlConn) writeCompressedPacket(data []byte, uncompressedLen int) err
 	data[3] = mc.compressSequence
 	putUint24(data[4:7], uncompressedLen)
 
-	if _, err := mc.netConn.Write(data); err != nil {
+	if _, err := mc.buf.writePackets(data); err != nil {
 		mc.log("writing compressed packet:", err)
 		return err
 	}

connection.go

@@ -33,7 +33,6 @@ type mysqlConn struct {
 	connector        *connector
 	maxAllowedPacket int
 	maxWriteSize     int
-	writeTimeout     time.Duration
 	flags            clientFlag
 	status           statusFlag
 	sequence         uint8

connector.go

@@ -132,8 +132,8 @@ func (c *connector) Connect(ctx context.Context) (driver.Conn, error) {
 	mc.packetRW = &mc.buf
 
 	// Set I/O timeouts
-	mc.buf.timeout = mc.cfg.ReadTimeout
-	mc.writeTimeout = mc.cfg.WriteTimeout
+	mc.buf.readTimeout = mc.cfg.ReadTimeout
+	mc.buf.writeTimeout = mc.cfg.WriteTimeout
 
 	// Reading Handshake Initialization Packet
 	authData, plugin, err := mc.readHandshakePacket()

packets.go

@@ -125,13 +125,6 @@ func (mc *mysqlConn) writePacket(data []byte) error {
 		if debugTrace {
 			fmt.Printf("writePacket: size=%v seq=%v", size, mc.sequence)
 		}
-		if mc.writeTimeout > 0 {
-			if err := mc.netConn.SetWriteDeadline(time.Now().Add(mc.writeTimeout)); err != nil {
-				mc.cleanup()
-				mc.log(err)
-				return err
-			}
-		}
 
 		n, err := mc.packetRW.writePackets(data[:4+size])
 		if err != nil {